Merge pull request duckdb#2604 from Mytherin/issue2599

Fix duckdb#2599: maintain correct dependencies between UNION ALL nodes so that output is deterministic/in-line with what a sequential execution would produce

Merge pull request duckdb#2371 from hannesmuehleisen/rpandoc

Installing pandoc so R pkg can be fully checked

Merge pull request duckdb#2247 from omo/setscope

Support session and global SET statement variable scopes.

Merge pull request duckdb#2082 from tiagokepe/master

ODBC: Allowing to pass nullptr value to SQLSetStmtAttr

Merge pull request duckdb#1849 from wangfenjin/sqlite3

Update sqlite3 wrapper for implement rust client

Merge pull request duckdb#1734 from hannesmuehleisen/pyscanrepgil

Need GIL for pandas scan replacement scope spelunking

Merge pull request duckdb#1478 from hannesmuehleisen/randomfix

Removing rand() from expression executor

Merge pull request duckdb#1352 from hannesmuehleisen/parquetmap2

Required Parquet fields within a list

Merge pull request duckdb#1184 from hannesmuehleisen/rprotect

Fix some R protection bugs

Update .travis.yml