fix: minor typos

feat(griffin): new algo for 'sample by .. fill none' without key. It executes a little faster than generic algo.

GRIFFIN: avg() implementation to address #78

fix: remove read of array element via unsafe - it is a slower method compared to conventional array read.

CUTLASS: improved text file ingestion performance via making text parser a little more optimal and not doing utf8decode on dates and timestamps where its not needed.

CUTLASS: refactored json processor to support INSERT and removed 'switch' in favor of O(1) method reference lookup

Fix database protocol name to follow most dominant OSS RDBMS

New readme

GRIFFIN: refactored insert statement implementation and tested exhaustively

GRIFFIN: tidy-up toString() invocations. I will cache those strings that are column or table names rather than making new string all the time.
GRIFFIN: assigned table name to InsertStatement so that it can be self-sufficient at execution time. Added tests for no timestamp and all partition types.
CAIRO: performance-optimised ByteSequence returned by VirtualMemory

GRIFFIN: removed duplicate code. Improved performance of symbol based filter, such as sym = 'XYZ' in cases where 'XYZ' does not exist. The cursor will not iterate over data if filter becomes constant.

GRIFFIN: timestamp_sequence() increment argument can be a function.

ALL: removed unused code

GRIFFIN: optimised 'and' and 'or' operators to recognise constant conditions better and avoid unnecessary data processing.
GRIFFIN: '=' impl for SYMBOL = CHAR, STRING = CHAR
GRIFFIN: 'sum' performance optimisation