Most relevant commits:
- builtin: add 'pow' builtin
- cmd/scriggo: update help
- cmd/scriggo: fix documentation printed by 'scriggo help import'
- all: add the README
- ast, compiler: refer to 'extends' and 'import' as declarations
- compiler: make {% import "path" %} an alias for {% import . "path" %}
- all: stop execution on context cancellation
- playground: prefix the error message with "panic: " on panic
- runtime: change 'Zero' instruction to implement the new specification
- compiler/checker: fix panic in case of redeclaration of imported name
- all: update the copyright statements
- cmd: add 'pow' built-in to the 'serve' command
- runtime: fail with a fatal error on go of nil func value
- compiler/checker: don't export names imported in file/package block
- compiler/parser: fix parse composite literal with no type as expression
- compiler/lexer: fix lexing closed braces in show statement
- compiler: support recursive extends