Fix issue with debug EosioTester builds

issues/4573 : Use of $JOBS instead of $CPU_CORE for make -j

Fix return value when throws connection_exception in cleos

Fix build script for Amazon Linux 2

Using $JOBS instead of the $CPU_CORE on make -j, preventing overuse/memory exhaustion when CPU is much higher than available memory.

This reverts commit 7d8d892e.

This reverts commit ec4ad250.

Fix bug that creates a gap in the syncing blocks

Added logic to prevent overuse of resources in make -j

 * remove block number comparison as it should be covered during the first comparison of the block_ids == operator
 * remove unused variable

Added SQL and ES plugin to COMMUNITY.md

When transitioning from the LIB sync mode to the mode where net_plugin catches up to the head of a remote peers best known branch, we calculate the branch to send based on the peers local LIB which could have shifted since the time the request was made due to latency.  If this it the first time we are synchronizing with that branch this means that there could be a gap in delivered blocks resulting in the blocks sent being unlinkable.   The more latency on a connection the more likely it is that the LIB of your block provider moved forward between the packets.

As a fix, we now send, at most, the branch from the LIB we last sent to that peer instead of the current LIB.  In addition, if that peer has reported its head id and we are building on top of that branch, we also squelch the delivery of blocks they already know about.

add state DB consensus indices during chain_plugin initialize rather than startup; use updated chainbase that ensures undo stacks are in sync among indices

fix replay with --disable-replay-opts

Update README for txn_test_gen_plugin 

 --http-validate-host=0 is required when launching the non-producer or curl requests will fail. 
keosd no longer adds the default private key to the wallet on creation. Manually add. 
Added link to the demo video

bump version to 1.3.0

PORT Consolidated Security Fixes for 1.2.6 to 1.3.0

Release 1.2.6

bump version to 1.2.6

Consolidated Security Fixes for 1.2.6

Fix trivial error message print in cleos http

- Consider peers for syncing at most once
Co-authored-by: NMatt Witherspoon <32485495+spoonincode@users.noreply.github.com>