Updated comments in lsh_index

It still had some comments from randomized kd-tree comments

C wrapper fix for C++99

Added index methods to C wrapper

Specifically the methods:
  * `addPoints`
  * `removePoint`
  * `getPoint`
  * `veclen`
  * `size`
  * `usedMemory`

Fixed compilation on Ubuntu 12.04

Sorry about last PR, this has been verified now

Added stdint.h so SIZE_MAX is defined

Solves a compilation issue for Ubuntu 12.04

result_set bugfix

fix constructor and deconstructor of the node of the hierarchical_clu…

Efficient compression

FLANN uses much less RAM when decompressing saved index files. Should be backwards compatible with original index type.

This bug will cause the serialization of the hierarchical_clustering_index to crash. Because when saving the index, the pivot and pivot_index for the top node of each tree is not initializaed. then when load these top nodes, pivot = obj->points_[pivot_index]; will cause error that index is out of range.

Edited python files to agree with pep8 standards

Replaced not 'a in i' to 'a not in i'
Replaced 'a == None' and 'a != None to 'a is None' and 'a is not None'
Replaced 'type(x) == type' to 'isinstance(x, type)'
Edited quotes to be consistent.
Replaced 'from x import *' with explicit imports
Used pep8 spacing in function signatures.
Changed classes to inherit from object
Removed unused imports

Zero-based boundary condition is not enforced for the variable size_t j,
it was previously free to underflow.

I have placed j-- as a condition within the for loop to enforce this.
See this
thread for considerations on good style for decrementing size_t loops:
http://stackoverflow.com/questions/7224386/iterating-with-size-t-0-as-a-boundary-condition

Placing the j-- at the beginning of the loop is equivalent to --j at the
end, so the functionality is identical.

Updated COPYING as this is standard / mandatory practice for Google employees'
contributions to open source projects.

fix constructor and deconstructor of the KDTreeIndex::Node. 

fix constructor and deconstructor of the KDTreeIndex::Node. This will cause the serialization work incorrectly in the case of the debug version and when the child pointer is not initialized as NULL automatically.

Because in saving node, serilazation relies on leaf_node = ((child1==NULL) && (child2==NULL)) to determine whether it's leaf or not.

Typo fix in heap.h

Typo fix

knnSearch (on vector<size_t>) missing const

abs -> std::abs

warning: using integer absolute value function 'abs' when argument is of
floating point type [-Wabsolute-value]

Fixed build error on VS 2013

unsigned __int64 ~= unsigned long long.  VS2013 will error.

link gomp only if openmp found

fix mingw x86_64 build

do not install flann matlab lib