tests/compile/compile.sh improvements (#1874)
tests/compile/compile.sh improvements (#1874)

tests/compile/compile.sh improvements
 * Allow running from either Blockly root or local dir.
 * Allow the use of npm google-closure-library.
 * Log compiler/library versions
 * Log full *compiler*.jar filename. Limit to one match.
 * Add npm instructions for both compiler and library.
 * Minor stylistic polish.
mark-friedman/blockly,trinketapp/blockly,twodee/blockly,nickmain/blockly,joshlory/blockly,google/blockly,trinketapp/blockly,mark-friedman/blockly,twodee/blockly,nickmain/blockly,joshlory/blockly,rachel-fenichel/blockly,picklesrus/blockly,picklesrus/blockly,rachel-fenichel/blockly,picklesrus/blockly,joshlory/blockly,google/blockly,rachel-fenichel/blockly,mark-friedman/blockly,nickmain/blockly,twodee/blockly,nickmain/blockly,google/blockly,google/blockly,twodee/blockly,nickmain/blockly,twodee/blockly,rachel-fenichel/blockly,mark-friedman/blockly,trinketapp/blockly,google/blockly,nickmain/blockly,twodee/blockly,rachel-fenichel/blockly,mark-friedman/blockly,trinketapp/blockly,mark-friedman/blockly,google/blockly,rachel-fenichel/blockly,rachel-fenichel/blockly,google/blockly